#include <stdlib.h>
#include <gtk/gtk.h>


//we will be swapping text1 and text2 between the text in the window and the window title
//I learned that I have to declare these arrays above any function will use them.
//Is there a "global" variable type?  Is that what "extern" is for?
char text1[50] = "I'm a pretty princess";
char text2[50] = "The rain in Spain";

static void killwindow (GtkWidget *window, gpointer data)
{
    //killwindow is our "exit" callback hooked to the "X"
    gtk_main_quit();
}

//swaptext basically just asks to see if the window title is already text2
//if it is, it switches text1 and text2, if not, vice versa.
//There is probably a far more graceful way of doing this.
static void swaptext(GtkWidget *window, GdkEvent *event, gpointer data)
{
    if (g_ascii_strcasecmp (gtk_window_get_title(GTK_WINDOW (window)),text2) == 0)
    {
        gtk_window_set_title (GTK_WINDOW (window), text1);
        gtk_label_set_text (GTK_LABEL (data), text2);
    }

    else
    {
        gtk_window_set_title (GTK_WINDOW (window), text2);
        gtk_label_set_text (GTK_LABEL (data), text1);
    }
}

int main (int argc, char *argv[])
{

    gtk_init (&argc, &argv);

  //our main window and text, respectively
    GtkWidget *window, *label;

    window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
    //don't forget to use the casting function GTK_WINDOW(window) or you'll get errors
    gtk_window_set_default_size (GTK_WINDOW (window), 500, 200);
    gtk_window_set_title (GTK_WINDOW (window), text2);
    gtk_window_set_resizable (GTK_WINDOW (window), TRUE);

    label = gtk_label_new (text1);
    gtk_label_set_selectable (GTK_LABEL (label), TRUE);

    gtk_container_add (GTK_CONTAINER(window), label);

    g_signal_connect (G_OBJECT (window), "destroy", G_CALLBACK (killwindow), NULL);
    g_signal_connect (G_OBJECT (window), "key_press_event", G_CALLBACK (swaptext), label);

    gtk_widget_show_all (window);

    gtk_main ();
    return 0;
}